Quickbooks Self Employed Business and Savings Accounts

Hello,

Not sure if I chose the correct topic, but I need some advice.

I set up QuickBooks Self-Employed a few years ago, which is connected to my personal checking account that I used to track both my business and personal transactions. My business income went to that account, as I didn't separate my personal from business back then. I have a personal checking account and savings account.

Now I have an LLC corporation. I have a business checking account and a business savings account that I have been using since October 2024. My bank set it up so that I can log into my banking and get access to all 4 accounts (business and personal) quickly.

My questions are:

1. What is the best way to set up QuickBooks for my Business account?  Do I need to include my business savings account?

I have business transactions during 2024 in my personal checking account--QuickBooks is still connected. I had/have business transactions going into my business account during 2024 and 2025--QuickbBooks not connected to my business account.

I don't want to remove my past QuickBooks transactions from my personal account that recorded my business income transactions in 2024 and part of 2025. I'll need this data for filing taxes--I'm filing late for 2024.

2. Would it be easier for me to purchase QuickBooks Self-Employed again to connect to my business checking and business savings account? 

When I give QuickBooks my banking username and password, it will include all 4 accounts (business checking & savings + personal checking & savings). I don't have a separate username and password for just my business account.  

3. Should I disconnect QuickBooks from tracking transactions in my personal checking account, now that I have all business income going into my business checking account?